Anticlog control for pumps



Dec. 1, 1931. D. CHURCH 1,834,333

ANTICLOG CONTROL FOR PUMPS Filed May 24, 1950 2 sheets-sheet 1 A TTORNEY5.

D66, 1, 1931. M D CHURCH 1,534,333

ANTICLOG CONTROL FOR PUMPS Filed May 24, 19:50 2 Sheets-Shei 2 INVENTOR. Mam/5K0 J]. (/UKCH.

K ff/M $102 A TTORNEYS.

Patented Dec. 1, 1931 UNITED s n s PATENT OFFICE- YNARD :o. CHURCH, or-wELLsvILLE, NEW YORK, assicnon TO MOORE STEAM run- JBINE'CORCPOR-ATION, F WELLSVILLE, YORK, A CORPORATION AN'rI'cLoG conrnotron rUMrs I Appl-icatiOn 'fihdMay24, 1930. 'Serial N0.455,192.

This invention relates to control apparatus for dredge pumps .or otherpumpsadapte ed for pumping. solids inv suspensionin a fluid. v

Such pumps are-,subject'to interruption inservice, Whenever the 'suction pipe, the pump itself or the discharge pipe becomes clogged With solid matter. Whenclogging starts, if the pump be immediately speeded up, the

corresponding increase in the velocity, inthe conduits, Will-tendto clear the obstruction before it becomes serious. The-object ofthe present invention is to provide -control apparatus Which automaticallyincreases. the

- speed of thepump When atendency toward clogging occurs andsby Which-the speedingup ismadesure, prompt and effective.v V

,The principal. feature of .theinvention by which this object is obtained resides in the provision of mechanism automatically .oper-z able in response'to changes in pressure caused by said cloggingtendency, said mechanism being aclaptedto increase the speed-setting of the governor of the-engine, turbine-or.

other motive means used to drivethe pump.

It is Well. known. that When clogging .begins in. the discharge pipe=.of:.a pump, :the discharge pressureat the pump willincrleas'e and-the vacuum in the suction pipe will decrease, i. e;-the absolute, pressure increases inboth, discharge and suction pipes. I When clogging begins in the suction pipe there verseis true and theabsolute pressure in {both pipes :is decreased. in; my -inv ention,these 1 changes in pressure are utilized to increase the speed of the pump, Whereas-pressure changes; occurring in 1 normal operation -do not necessarily aflect thesa-id speed.

Other objects and featureswill be :under-.

stood fromthe accompanying drawingsand the following description-andclaims; v

Rig, 1 is ii-diagrammatic representation illustrating the invention as applied to a. cen

trifugal pump driven by a steam turbine having a hydraulically-operated governor.

Fig.2 is across sectional view 'of a preferred form of governormechanism for use with, the turbine of Fig; Fig. 3. is a sectionalview of a preferred form of certain of the control apparatus hereinafter des'cr-i-bed.-

Fig. 4:.is a diagrammatic representation illustrating the invention as applied to.v acentrifugal pump driven by'areciprocating engine having a common form of fly-ball governor. Fig. 5 is a diagram of apparatus and: electrical connections for the application of theinvention to a pump driven-by a direct. current electric motor. I

In Fig. ,1 a centrifugal dredge pump 10,. having an inlet pipe 11 and an outlet pipe,12, is. driven by a steam turbine 13. bymeansof suitable speed reduction gears contained in a gear housing 14.. The turbine v 13 isfitted with a governor valve 15 for-controllingthe flowof steam from a steam pipewl6 to the V turbine and pump.

Thegovernor valve 15is preferably of the balanced type illustrated in Fig; 2 and is fitted with a valve member 17. having portions 18 and 19 adapted to engage seat por- V tions- 20 and 21 respectively of the valvehousing. .When said portions are not in engage ment steam may flow through the valve to; the turbinev as indicated bythe arrows-in Eig 2. -As the valve member 17-is movedto the left referring to Fig. 2, the flow of steam; is

reduced and, upon the engagement of said valveportions flow of. steam is stopped. 'The governor valve is also fittedwitha butterfly; valve .22. for stopping the; turbine. in an emergency independently of the movement of.

valve member .17. I p I H e The valve member :17 is movable by means of a val ve stem 23 passing through astuifing,

box 24 in the valve cap casting 25. The said casting has a portion 2 6 terminatingina flange 27 to. which is attached a housing28 formingwiththe flange 27, a chamber 29. The valve stem 23 extends through an {opening 30 in flange 27 into the chamber 29 and terminates in a spring seat 31 to which is attachedv a disc. member 32. The said disc member '32 has fastened thereto one end of a member 33 in the form of a corrugated cyl-' meter of flexible material, the opposite "end of'Which terminates in an outWa-rdly turned flange -34 caught between the flange 27"and housing 28. By this means the chamber'29 is divided into a portion Within the corrugated member 33 and a portion outside of said member. lf hydraulic pressure is applied in the latter portion, the tendency thereof is to act upon the disc 32, to collapse the corrugated member 33 and close valve 15. A. helical spring 35 is interposed between flange 27 and spring seat 31 and normally tends to resist the closing of said valve.

A governor pump 36, herein shown as common form of gear pump, is driven by the turbine 13 and supplies oil or other suitable liquid from a reservoir 37 by means of pipes 38 and 39 to the outer portion of chamber 29.

A by-pass 40 leads from pipe 39. to the reser-.

voir 37 and is fitted with a needle valve 41 for controlling flow of Oll therethrough. A second-by-pass consisting of pipes 42 and 43 also leads from pipe 39 to reservoir 37 and is controlled by a valve 44, the operation of which is hereinafter described. In the normal operation of the pump 10, when no clogging tendency is present and a constant speed is desired, the valve 44 is closed and no flow is present in by-pass 42-43. The governor pump 36 then circulates oil from the reservoir 37 through pipes 38 and 39 and by-pass 40 back to the reservoir. For a given setting of needle valve 41, the pressure pipe 39 and chamber 29 depends entirely upon the speed at which the pump 36 is driven by turbine 13. An increase of turbine speed above the desired limit increases the pressure in chamber 29, thus moving the valve member 17 against the action of spring 35 to reduce the flow of steam through valve 15 and correct the turbine speed. A decrease of turbine speed below normal operates to reduce the pressure in chamber 29, to allow opening of valve 15, to return turbine speed to normal. Thus the arrangement of elements just described oper ates to maintain a substantially constant turbine speed so long as no flow is allowed through valve 44. If, however, the valve 44 is opened, the pressure in pipes 39 and chamber 29 is immediately reduced, opening governor valve-15 and causing an immediate increase in turbine speed.

The valve, 44 comprises a housing 45 divided by a partition 46 into an inner chamber 47 communicating with pipe 42 and an outer chamber .48 communicating with pipe 43. The said partition is provided with an upper port 49. and a lower port 50; A valve stem 51 is provided with an enlarged cylindrical portion 52 adapted to engage and close both ports 49 and 50 when in the normal position illustrated in Fig. When the said valve stem is downwardly moved, port 49 is opened and, when upwardly moved, port 50 is opened. Movement of the stem 51 in either direction from the normal position therefor permits flow of oil through by-pass 4243 to increase the turbine speed.

The valve 44 is mounted upon a plate 53 to which is attached a pair of downwardlyextending cylindrical members 54 and 55 terminating in flanges 56 and 57 respectively. A flexible diaphragm 58 is inserted bet-ween flange 56, and a flange 59, forming a part of a housing 60 and bolted to said flange A similar diaphragm 61 is placed between flange 57 and a flange 62 forming a part of a housing 63. and boltedto said flange 57. A stem is attached to diaphragm 58 bymeans of plates 65 and 66'and is attached at its upper end to a member 67 in turn fastened to a stem 68. The upper end of stem 68 is threadedly engaged with a hand wheel 69 abutting against a spring seat 7 O. A compression spring71 is interposed between said spring seat and the upper surface of plate 53. A stem 72 is connected at its lower end to a plate 73 abutting against the upper surface of diaphragm 61. The said stem is attached at its upper end to a member 74 in turn fastened to a spring seat 75. A helical compression spring 76 is interposed between said spring seat and an upper spring seat 7 7 The lastmentioned spring seat is engaged by the lower end of a vertical stem 78 threadedly engaged with a yoke member 79 forming a part of the plate member i A hand wheel 80 is fixed to the upper end of the stem 78 for rotation thereof. A beam member 81 is pivotally connected adjacent one end to the member 6?, adjacent the opposite end to the member 74 andat an intermediate point to the lower end of valve stem 51. Indices 82 are placed adjacent the pointed ends 83 of beam 81 to indicate the normal position of said beam, in which position the valve stem 51 is in the proper position to close completely the ports of valve 44. The housing 60 and diaphragm 58 form a chamber 84 which communicates by means of a pipe 85 With the intake pipe 11 of the dredge pump 10. The housing 33 and diaphragm 61 form a similar chamber 86 which communicates by means of a pipe 82" with the outlet pipe 12-of the-pump 10.

In starting the pump 10, a valve 88 in pipe 42 is closed, the turbine is 1 supplied with steam and the needle valve 41 is adjusted untilthe turbineand pump assume the de sired normal speed. The hand wheels 69 and 80 are then adjusted to-bring the ends 83 of beam 81*to the indices 82 indicating that valve 44 is completely closed. The valve 88 may then be opened without affecting the speed of the turbine so long as the pressures in the inlet and outlet pipes 11 and 12 and hence in chambers 84 and 86 remain un changed. 9

In the normal operation of the pump, a varying amount of suspended solids are carried by the. liquid passing therethrough. When the amount of said solids is greater than normal, there is an increase of pressure in outlet; pipe 12 and chamber 86 accompanied by a corresponding increaseYin vacuum or decrease in pressure in theintake pipe 11 and chamber-84. Withinpractical limits, the increase in outlet pressureand the decrease in inlet pressure are directly :pro-. portional for a given. change in the fluidity of the mass. The said pressure changes are not necessarily equal, however, since their actual values depend upon the dimensions of'the intake and discharge pipes. .These pressure changes cause an upward movement of diaphragm 61 against the pressure of spring? 6 and a downward movement of diaphragm 58 against the pressure of spring 71-. The diameters of the chambers 86 and 84, the position of the connection between stem 51 and beam 81 and the characteristics of the said springs are so chosen in relation to the pipe sizes that these movements result in a pivotal movement of beam 81 about its connection with valve stem 51, no motion of the said valve stem results and the speed of the turbine is unchanged. A decrease in the amount of suspended solids similarly results in a downward movement of diaphragm 61' and an upward movement of diaphragm-58, again resulting in a. simple pivoting motion of beam 81- and not aflectingturbine speed. Under normal pump operation, therefore, normal turbine and pump speeds are maintained. It is to be noted that the corresponding changes of suction pressure and discharge pressure under these conditions need not be equal in order to produce the re sults described, since the said results are controlled by suitable choice of proportion of parts and characteristics of springs.

If a tendency toward clogging develops in the outlet pipe 12, the pressure therein is increased. Since the clogging causes a decrease in the rate flow of material,-the vacuum in the inlet pipe 11 also decreases. These pressure changes result in an upward movement of both diaphragms 58 and 61 or an upward movement of one unaccompanied by a corresponding downward movement of the other. is upwardly moved, opening valve 44, allowing oil to flow through by-pass 4243, reducing pressure in chamber 29 and thereby immediately increasing the speed of the turbine and pump to a speed sufficient to clear the clogging material from the pipe 12.

If a tendency toward clogging develops in the inlet pipe 11, there is an'immediate increase in the vacuum therein accompanied by a decrease of pressure in pipe 12.' There is, therefore, a downward movement'of both diaphragms, or a d'ownwarchmovementof one unaccompanied by a corresponding upward movement of the other. The valve stem 51 is, therefore, moved downwardly, the valve 44 is opened and the speed of the turbine increased as before toremove theclogging material. Upon the clearingof the- In either case the valve stem 51 a steam pipe 119. A support .member 114 is carried upon the frame of the engine 113 and supports a fly ball governor 116*.and. associated driving apparatus 117 of any "well known form. Thesaid governoris adapted to move a lever 118 inv response tovariations in-engine speed. The said lever is pivotally carried upon an. arm 120 of the support mem ber 114 and is pivotally connected-at oneend to a downwardly-extending link 121. The said link is pivotally connected to one end of a lever 122, inturn pivotally connected to the stem 123 of valve v115 and pivotally carried by anarm 124 forming a part of the housing of said valve.

The lever 118 has attached to its opposite end a helical spring 125 in turn attached to. one end of a lever 126. The opposite end'of lever 126 is pivotally carried byanysuitable stationary support 127 and has pivotallyconnected thereto a stem 128 extending-within a housing 129 containing mechanism similar.

in construction and function to that in chamber-29 previously described. By means of this construction, the governor116 maintains the speed of engine and pump at thedeslred normal value so long as a given constant pressure is maintained within'the housing 129.-

An increase in said pressure, however, acts to move lever 126 downwardly, therebyexerting a force upon lever 118 through spring 125 tending to open valve 115. and increase the engine speed. 7

A pipe 130 is connectedto any suitable supply of a liquid under a predetermined pressure and supplies said liquid toa valve 144 similar in construction. to valve 44. A pipe 131 connects said valve to the chamber 129; A branch 132 leads from pipe 131-to a needle valve 133. Excess liquid is discharged from the said needle valve through a pipe 134.

By this means, the pressure in'chamber 129 1- remains at substantially atmospheric pressure so long as valve 144 is'closed.

upon the rate of escape of liquid through the The opening of saldvalve. causes an increase of; said pressure,the amount of which depends 144and the operation of said apparatus is exactly. similarto that-for actuating valve 44 and will not be again described in detail. The normal variations in inlet and outlet pressures do not effect an opening of valve 144 while pressure changes due to clogging in the inlet or outlet pipes cause opening of valve 144 and an increase in the speed of engine and pump in the same manner as heretofore described.

Fig. 5 is a diagram of apparatus and electrical connections for the application of the invention to a pump driven by a direct current electric motor. In the said figure, the motor for driving the pump has an armature 210, series field 211, and shunt field 212. Power therefor is supplied upon power lines 213 controlled by cutout switch 214. One pole of the switch 214 is connected to the armature 210 by means of a wire 215 and the opposite pole of said switch is connected to series field 211 by means of a wire 216. One terminal each of the armature, shunt field and series field are connected together in the usual manner. The opposite terminal of the shunt field 212 is connected by a wire 217 with a resistor 218 and a normally closed Contact element 219. The contact element 219 forms part of a double pole magnetic relay having a normally open contact element 220 connected by a line 221 to the opposite terminal of the resistor 218.. The said relay is actuated to close the contact element 220 and open the contact element 219 by the energizing of a magnet 222. One terminal of the said magnet is connected to the midpoint of the relay and to the switch 214 by means of a wire 223. When the said magnet is deenergized, the shunt field circuit for the pump motor is as follows: 213, 214, 223, 219, 217, 212, 211, 216, 214, 213. The resistor 218 is, therefore, not in the circuit and the motor operates at its normal speed. Vhen the magnet 222 is energized, the resistor is placed in series with the shunt field by means of the following circuit: 213, 214, 223, 220, 221, 218, 217, 212, 211, 216, 214, 213. The motor then operates at an increased speed.

The second terminal of the magnet 222 is connected by a wire 224 to a pair of station'- ary contact members 225 and 226 having associated therewith a movable contact member 227. The member 227 is connected by a wire 228 to the switch 214 and is carried upon the upper arm of a bell crank 229, the opposite arm of which is attached to a vertical stem 230. The stem 230 is actuated by mechanism indicated generally by the numeral 281 which is exactly similar to that by means of which the stem 51 is actuated for the operation of the valves 44 and 144, previously described. The mechanism 231 is connected to the pump in the same manner as that previously described and operates to maintain the contact member 227 out of engagement with the contact members 225 and 226 for normal opera-- tion of the pump. When clogging occurs the'suction or discharge pipe of the pump, the resulting pressure changes cause contact member 227 to engage one or the other of the members 225 and 226, energizing the magnet 222 and increasing the speed of motor and pump to remove the clogging material from the said conduits. Other suitable wiring connections are used to apply the invention to alternating current motors.

Obviously other variations in the application of the invention and the details of the apparatus disclosed are possible Without departing from the broader features of the invention as set forth in the following claims. In the claims, the use of the word pressure refers to absolute pressures.

The invention claimed is:

1. The combination of a pump, an inlet and an outlet pipe therefor, motive means for said pump, and mechanism adapted to increase the speed of said pump, said mechanism being automatically operable in response to an increase of pressure in said outlet pipe only when unaccompanied by a corresponding decrease of pressure in said inlet pipe.

2. The combination of a pump, an inlet and an outlet pipe therefor, motive means for sait pump, and mechanism adapted to increase he speed of said pump, said mechanism being automatically operable in response to a decrease of pressure in said outlet pipe only when unaccompanied by corresponding increase of pressure in said inlet pipe.

8. The combination of a pump, an outlet and an inlet pipe therefor, motive means for said pump, and mechanism adapted to increase the speed of said pump, said mechanism being automatically operable in response to an increase of pressure in said inlet pipe only when unaccompanied by a corresponding decrease of pressure in said outlet pipe.

4. The combination of a pump, an outlet and an inlet pipe therefor, motive means for said pump, and mechanism adapted to in crease the speed of said pump, said mechanism being automatically operable in response to a decrease of pressure in said inlet pipe only when unaccompanied by a corresponding increase of pressure in said outlet pipe.

5. The combination of a pump, inlet and outlet pipes therefor, motive means for said pump, a speed governor for said motive means, a fluid operated device for modifying the setting of said governor, a valve for controlling the flow of fluid to said device, movable member for operating said va ve, said valve being adapted to be similarly operated by movement of said member in either direc tion from a predetermined normal position, and mechanism for automatically moving said member in one direction from said normal position when clogging of saidinlet pipe occurs and for automatically moving the same from said normal position in the opposite direction when clogging of said outlet pipe occurs.

6. The combination of a pump, inlet and outlet pipes therefor, motive means for said pump, a speed governor for said motive valve operating member and extending transversely thereof in both directions from the point of said attachment, and a pressure responsive device operably associated with each end of said lever, one of said pressure responsive devices being adapted to move one end of said lever in one direction when pressure in said outlet pipe increases and in the opposite direction when said pressure decreases and the other of said pressure responsive devices being adapted to move the opposite end of said lever in the first-mentioned direction when pressure in said intake pipe increases and in the opposite direction when said intake pressure decreases.

7. The combination of a pump, inlet and outlet pipes therefor, an electric motor for driving said pump, an electric switch, electrical connections between said switch and said motor adapted to increase the speed of said motor when said switch is operated, a

movable member for operating said switch,

said switch being adapted to be operated for increasing the speed of the motor by moveber in one direction from said normal po-- sit] on when clogging of said inlet plpe occurs and for automatically moving the same from said normal position in the opposite direction when clogging of said outlet pipe occurs.

8. The combination of a pump, inlet and outlet pipes therefor, an electric motor for driving said pump, an electric switch member, electrical connections between said motor and said switch for increasing the speed of said motor when said switch is operated. a movable member for operating said switch, said switch being adapted to be operated for increasing the speed of said motor by movement of said member in either direction from a predetermined normal position, a lever pivotally attached to said switch-onerated member and extending transversely thereof in both directions from the point of said attachment, and a pressure-responsive device operatively associated with each end of said lever, I

one of said pressure-responsive devices bemg connected to said outlet pipe, and being adapted to move one end of said lever in one direction when pressure in said outlet pipe increases and in the opposite direction when said pressure decreases, and the other of said pressure-responsive devices being connected to said inlet pipe and being adapted to move the opposite end of said lever in the firstmentioned direction when said pressure in said intake pipe increases and in the opposite direction when said intake pressure de-' creases.

In witness whereof, I have hereunto afiixed my signature.

MAYNARD D. CHURCH. 

